Yooper said:No. You want to convert the starches to fermentable sugars, and that happens during the mash. During the sparge, you rinse those sugars away from the grain. If there is any efficiency gain by resting during the sparge, then there is a problem somewhere (and not with the sparge).
Does letting it rest increase efficiency of sugar and protein extraction? Cuz I would definitely shorten my rest period (10-15min now) to save some more time if it doesn't matter.
From what I've read on this forum and from my own experience I doubt it really matters all that much. I drain off my first runnings, add the sparge water, stir and let it set for 15 minutes, vorlouf and drain it off. Efficiency is good, beer is good. Happy camper.
Conflict, conflict, conflict. J/K. My mash tun is a 22 qt pot, my lauter tun is a Zapap bucket system to lauter/ sparge. I am stiill a new brewer with less than 20 batches under my belt, and am I still my own worst critic. For my pieced together system, I didn't start getting good O.G. numbers, until I took more time to vorlaugh, and addition of sparge water let go for 10 minutes.
If you need to vorlauf more than a couple of quarts, there is something not right with the false bottom/braid/whatever separation medium. I do 10 gallon batches, and never need to vorlauf more than two quarts, even with a very fine crush.